Like most undergraduates in physics, I'm passionate about what I study and very much would like to have a career as a physicist. However, while I don't mind being poor, I don't want to have to struggle to get hired. I'm also really interested in theoretical work, but I have been admonished that such pursuits can be career-killers. However, I've been looking into nanotech (and other fields at the crossroads between chemistry and physics, like condensed matter physics and chemical physics), and it seems that there are some good research opportunities combining both laboratory and theoretical work. I wanted to know if a) that there's still theoretical work done in nanotech fields, and that it's not just fiddling in a lab, and b) that the theory behind nanotech is physics-based, and that I won't find myself having to study biology instead of quantum mechanics. Thanks.